Transcription

1 Introduction ATOMIC STRUCTURE The concept of an atom is originated from Greek philosophers like Democritus and John Dalton. Democritus studied the nature of matter and the constituents of all the substances. In 1808 John Dalton put forward atomic theory to explain the laws of chemical combination. According to him, an atom is the smallest unit of matter which takes part in a chemical reaction. He considered that atoms are indivisible particles At the end of 18 th and early 20 th centuries modern concept an atom developed by scientists like J.J Thomson, Gold stein, Ruther ford, Bohr and others. Modern concept of an atom Atom consists of smaller particles (sub atomic particles ) like electron, proton and neutron. These particles are called as fundamental particles. The atom contain nucleus at its center,which has positively charged protons and neutrons Electrons are revolving around the nucleus and they carry negative charge. Fundamental particles of an atom 1.electron (e - ) J.J Thomson discovered electrons in 1897 Mass of electron = x g =9.107x10-31 kg Charge of electron = Unit negative charge =1.602x10-19 coulombs The charge of e - was measured by R.A. Millikan in proton E.Goldstein discovered proton in 1836 Mass of proton =1.672x10-24 g =1.672x10-27 kg Page 1 of 5

2 Charge of proton =Unit positive charge =1.602 x neutron James Chadwick discovered neutron in 1932 Mass of neutron =1.675x10-24 g =1.675x10-27 kg Charge of neutron =carry no charge i.e. neutral Concept of orbit and orbitals Orbit: orbit is a well defined circular path around the nucleus in which an electron revolves. Orbit of definite energy levels called shells.these shells are named as K,L,M and N and numbered as 1,2,3, and 4 respectively from the nucleus. An orbit (shell) can accommodate electrons equal to 2n 2. For K Shell, n =1 maximum no of e - s in K shell =2n 2 =2(1) 2 =2 Therefore maximum no of e - s in K shell = 2 Similarly for L shell, n = 2, Therefore maximum no of e - s = 8 for M shell n =3, Therefore maximum no of e - s =18 for N shell n = 4, Therefore maximum no of e-s =32 Orbital :Orbital is the three dimentional region around the nucleus where the probability of finding electron density is maximum.all orbitals have definite shape and each can accommodate maximum of two electrons in it. Orbital are named as s, p, d and f. s orbital can accommodate 2 electrons.there are three p orbital, each can accommodate two electrons therefore totally p orbital can accommodate 6 electrons.there are five d orbital so it can accommodate maximum of 10 electrons and there are seven f orbital and it can accommodate14 electrons. Page 2 of 5

3 Energy level Diagram The relative energies of various orbital can be shown by an arrangement is called as energy level diagram. Schematic diagram to remember sequence of filling atomic orbitals. Page 3 of 5

5 7. Who discovered Proton? 8. What is the Mass of Proton? 9. What is the charge of Proton? 10. Who discovered Neutron? 11. What is the Mass of Neutron? 12. Do the Neutron have charge? 13. What is an Orbit? Mention different Orbits. 14.How many number of electrons can be accommodated in (a) L Shell (b) N Shell 15. Write the formula to accommodate maximum number of electrons in a shell. 16. What is an Orbital? Mention different Orbitals. 17. What do you mean by Energy Level Diagram? 18. Write the schematic Diagram to remember sequence of filling atomic orbitals. 19. Write the Electronic configuration for the following elements. (a) Nitrogen ( Atomic number 7 ) (b) Magnesium ( Atomic number 12 ) (c) Argon ( Atomic number 18 ) (d) Calcium ( Atomic number 20 ) Page 5 of 5

1. Structure and Properties of the Atom 1.1 Atoms: A simple definition of the atom is that it is the smallest particle that contains the properties of that element. The idea of atoms was first suggested

SACE Stage 1 Chemistry - The Essentials 1. Structure and Properties of the Atom 1.1 Atoms: A simple definition of the atom is that it is the smallest particle that contains the properties of that element.

Name: Date: 1. Which of the following best describes an atom? A. protons and electrons grouped together in a random pattern B. protons and electrons grouped together in an alternating pattern C. a core

ATOMIC THEORY The smallest component of an element that uniquely defines the identity of that element is called an atom. Individual atoms are extremely small. It would take about fifty million atoms in

What do you know about atoms? On your paper, draw and label the parts of the atom Protons Electrons Neutrons Nucleus Electron Cloud Here is the model of an ATOM! Check your drawing and correct Atoms Everything

Name Date STUDY GUIDE CHAPTER 1 ATOMS AND ELEMENTS 1) DESCRIBE THE RUTHERFORD-BOHR ATOMIC MODEL All matter is made of small particles called atoms. An atom is the smallest unit of matter that retains the

Q1. Dalton and Thomson each proposed a model of an atom. a What experimental evidence did Thomson have that was not available to Dalton? b As a result of this experimental evidence, how did Thomson s model

Chemistry CP Unit 2 Atomic Structure and Electron Learning Targets (Your exam at the end of Unit 2 will assess the following:) 2. Atomic Structure and Electron 2-1. Give the one main contribution to the

1. MODERN MODEL OF THE ATOM A. A Closer Look at the Nucleus Since Bohr, the model of the atom has become even more sophisticated. Scientists had to explain why even the thin lines in an emission spectrum

7.4 Using the Bohr Theory LEARNING TIP Models such as Figures 1 to 4, on pages 218 and 219, help you visualize scientific explanations. As you examine Figures 1 to 4, look back and forth between the diagrams

Science of Kriyayoga IST 111-01, Spring 2005 Matter, Elements, Compounds, Chemical Bonds and Energy In our discussion so far, we have discussed human nervous system and cell biology, in addition to the

CHAPTER 4 2 The Structure of Atoms SECTION Atoms KEY IDEAS As you read this section, keep these questions in mind: What do atoms of the same element have in common? What are isotopes? How is an element

Introduction to Chemistry Chapter 5 1 Atoms, Molecules, Formulas, and Subatomic Particles The Atom: The smallest particle of an element that can exist and still have the properties of the element building

Atomic Structure ELECTRONS AND THE STRUCTURE OF ATOMS 4.1 Defining the Atom Essential Understanding Atoms are the fundamental building blocks of matter. Lesson Summary Early Models of the Atom The scientific

Unit 2: Atomic Theory Practice Packet 1 Name History of Atomic Theory Period Fill in the missing information in the chart below: Name of Researcher Equipment Sketch of Model Major Idea/Discovery N/A All

Section A Q1 The first six ionisation energies of four elements, A to D, are given. Which element is most likely to be in Group IV of the Periodic Table? Q2 In which species are the numbers of electrons

THE ATOM HISTORY AND STRUCTURE Atom- The smallest unit of an element that maintains the properties of that element. Originated from the Greek word Atomos - meaning indivisible particle. Ancient views of

Name: Class: Date: Chapter 4 Review 1. According to, all matter was made up of four elements: earth, air, fire, and water. 2. Unlike Democritus, Aristotle did not believe that matter was composed of tiny,

1. According to the modern model of the atom, the nucleus of an atom is surrounded by one or more 8. The diagram below represents the nucleus of an atom. A) electrons B) neutrons C) positrons D) protons

Name: Date: 1. In the modern Periodic Table, the elements are arranged in order of increasing A. atomic number B. mass number C. oxidation number D. valence number 6. As the elements in Group IA are considered

Chapter Five: Atomic Theory and Structure Evolution of Atomic Theory The ancient Greek scientist Democritus is often credited with developing the idea of the atom Democritus proposed that matter was, on

Periodic Table Extra Practice 1. Which of the following elements in Period 3 has the greatest metallic character? 1) Ar 3) Mg 2) Si 4) S 2. Which sequence of atomic numbers represents elements which have

Name: Monday, October 15, 2007 Test 2: Atomic Structure Review 1. Figure 1 The diagram shows the characteristic spectral line patterns of four elements. Also shown are spectral lines produced by an unknown

During Class Invention Question: How are electrons arranged in an atom? 1. Describe the nature of the interaction between protons and electrons in an atom? Consider using some or all of the following terms

The Periodic Table: Chapter Problems Periodic Table 1. As you move from left to right across the periodic table, how does atomic number change? 2. What element is located in period 3, group 13? 3. What

Introduction to Atoms What is the smallest particle into which an element can be divided and still be the same substance? A. electron B. neutron C. proton D. atom What is the smallest particle into which

Protons, Neutrons, and The diagram shows a model of an atom. It shows the nucleus, protons, neutrons, and electrons. The diagram is not to scale. Label a proton, a neutron, an electron, and the nucleus.

Name: Work hard. Be nice. Period: Date: Hybrid Chemistry Regents Prep Ms. Hart/Mr. Kuhnau UNIT 1: All about Atoms Lesson 1.3: Electrons! By the end of today, you will have an answer to: What is electron

Biology 1 of 40 2 of 40 Atoms Atoms The study of chemistry begins with the basic unit of matter, the atom. The Greek philosopher Democritus called the smallest fragment of matter the atom, from the Greek

7.1 Atoms and Isotopes The history of atomic discovery begins with the ancient Greeks, when, around 400 BCE, philosopher Democritus asserted that all material things are composed of extremely small irreducible

1. Which statement best describes Group 2 elements as they are considered in order from top to bottom of the Periodic Table? (A) The number of principal energy levels increases, and the number of valence

reflect Suppose you wanted to organize your locker at school. How could you separate and arrange everything in an organized way? You could place the books, notebooks, and folders on a shelf that is separate

Periodic Table Science 7 2015 ??? From an elements location in the periodic table, you can predict properties From an elements location in the periodic table, you can predict ??? Most metals are this state

1301 TEST 1 REVIEW SHEET You need to read chapters 1 through 4 All is fair game unless I announce otherwise on Wednesday before the test. Introductory Stuff Scientific Method Atoms and Molecules; Dalton

Atomic Structure 1. What is the total number of electrons in the 2p sublevel of a chlorine atom in the ground state? (1) 6; (2) 2; (3) 3; (4) 5. 2. Which is the electron configuration of an atom in the

ANSWERS: Structure 1. Al 3+ because it has 13 protons (+ charges) and only 10 electrons ( charges). It has only 10 electrons, as its electron arrangement as an atom was 2,8,3, and when it forms an ion,

CP Biology 2016 Name KEY UNIT 2A: Basic Chemistry Chapter 2: The Chemistry of Life 2.1 The Nature of Matter The Structure of an Atom Living things share a major fundamental similarity with nonliving matter.

ELECTRON CONFIGURATION and BOHR-RUTHERFORD DIAGRAMS I. Electron Arrangement. The electron configuration is a way of showing how the electrons are arranged in an atom. Recall that electrons are placed in

Periodic Table Questions 1. The elements characterized as nonmetals are located in the periodic table at the (1) far left; (2) bottom; (3) center; (4) top right. 2. An element that is a liquid at STP is

Name: Period: Date: Unit 3 Review: things you will need to know 1. Atomic Theories: Know all the scientists in order. What did they discover? What experiment did they use? 2. Development of the periodic

Basic Chemistry Why do we study chemistry in a biology course? All living organisms are composed of chemicals. To understand life, we must understand the structure, function, and properties of the chemicals

ATOMIC STRUCTURE AND THE PERIODIC TABLE CHAPTER 4 WORKSHEET PART A Given the following isotopes, determine the atomic number, the mass number, the number of protons, electrons and neutrons. Isotope Symbol

Unit 1 The Periodic Table: Periodic trends There are over one hundred different chemical elements. Some of these elements are familiar to you such as hydrogen, oxygen, nitrogen and carbon. Each one has

Chemistry: Atomic Structure Organization of the Modern Periodic Table The periodic table is organized by properties. The Atom Today atom = All atoms of the same element are essentially (but not exactly)

Chapter 2 1 Chapter 2 Atoms and the Periodic Table Solutions to In-Chapter Problems 2.1 Each element is identified by a one- or two-letter symbol. Use the periodic table to find the symbol for each element.

1. The atomic number of an atom is always equal to the total number of A. neutrons in the nucleus B. protons in the nucleus 2. All of the atoms of argon have the same A. mass number B. atomic number C.

Surviving Chemistry One Concept at a Time Atomic Structure Organized and Engaging Worksheets for High School Chemistry Atomic Structure Worksheets One Concept at a Time Worksheets for High School Chemistry

Part I: Principal Energy Levels and Sublevels As you already know, all atoms are made of subatomic particles, including protons, neutrons, and electrons. Positive protons and neutral neutrons are found

Biology Summer Work 2015: This packet has been put together by your Biology teachers for you to work on during the summer. It will help you review topics that you have learned in 9 th grade and will help

Chapter 3 Atoms and Elements 1 Elements Elements are pure substances that cannot be separated into simpler substances by ordinary laboratory processes the building blocks of matter listed on the inside

How many protons are in oxygen? 1 What is the atomic mass of Iridium? 192 What is the number of protons and neutrons in Niobium? 93 How many electrons in Potassium? 19 What is the atomic number Chromium?

CHEM100 Week 4 Notes Page 1 of 6 Scientists create models to understand how things work, including atoms. Dalton created a theory for the atom with these 5 postulates 1. Elements consist of one or more

Unit 3 Review Chapters 4 (Atomic Structure) & 6 (Periodic Table) Part 1: Answer the following questions. 1. a. Which scientist created the first modern atomic theory? John Dalton b. What was his theory?